Most Powerful Monster

Chapter 13

Sans's POV

I teleported to the inside of the Ruins. I hated leaving (Y/N), but I didn't want anything to happen to her or Papyrus. I'm sure she was going to try to break out, so I used some magic to lock all the windows and outside doors. I found myself in front of an adorable, purple-brick house. Maybe this is Toriel's home. Perfect. I hoped Toriel was OK. I swung open the door, left eye and hands blazing in case Chara decided to do a sneak-attack. I looked around warily. I walked into what looked like a living room.

A pair of demonic giggles sounded behind me. I swiveled around with narrowed eyes. Flowey and Frisk stood in the middle of the long hallway. Frisk's eyes were open and were a bright red color. They were sliding their index finger along the flat side of a long knife. Both Flowey and Frisk gave me evil smiles. "Why hello, Sans," Flowey snickered in his stupid high-pitched voice. I stared daggers at them which only made them laugh more. I punched upwards, summoning a huge wall of bones under their feet. Even though they were expecting it, they couldn't jump up fast enough, getting hit a few times. They glowered at me while I just shrugged. Frisk launched themself at me, swinging their knife left and right. I smiled as I dodged every single swing. On their last swipe, I spun behind them, summoned a long bone in my hand, and launched it at them like a spear. They dodged and swung again but missed. I then kicked Frisk back towards Flowey, summoned a line of Gaster Blasters behind me, and shot at them. They threw themselves to the ground and barely missed the deadly attack. Flowey then cackled, and vines started shooting up from the ground around me, attempting to grab me. I dodged all of them with ease. I then called on another Gaster Blaster to disintegrate them. Out of nowhere, a long, whip-like vine with huge thorns burst through the ground in front of me and swiped at me. I scrambled away from it, but it came back around and whipped me across the face. I yelped and put a hand where it hit me: a long diagonal long right across the front of my face. I don't know how the thorns were sharp enough to cut through bone, but it did. I removed my hand to find bone marrow stained on my fingers. The vine tried to get me again, but I snapped my fingers, and a Gaster Blaster came and finished it off. I glared at Flowey who was smiling that he finally landed a blow on me. "You'll never win. This time, Chara is helping me. I'll beat you this time!" Flowey vowed. I smirked at his confidence. I thought I was, 'the most powerful monster in the Underground'? He's just getting cocky. It took him many RESETS but still failed. What makes him think he can do it now? Is it because he has Chara helping him? That may be an advantage, but I'll make sure he doesn't get past me.

"Whatever you say, buddy," I replied breezily. I reached my arm out towards Flowey and Frisk, and a cage made of bones surrounded them, inching closer to them. I then summoned a Gaster Blaster on the top of the cage, firing into it. Flowey and Frisk smashed themselves into the walls of the cage to avoid the poisonous beam, but they still managed to get hit by it. I waved the Gaster Blaster and cage away. Flowey and Frisk looked really mad. Now, they decided to be smart and attacked me at the same time. Vines shot up around me as Frisk tried to cut me down. I ducked away from the vines and dodged left and right from Frisk. I made a really stupid mistake and cornered myself, Frisk in front of me with vines creeping towards me on all other sides. I kicked Frisk away again, vines above tried to impale me, and more vines from the left and right tried to wrap around my arms and legs. Somehow, I managed to dodge all of them. I ran out of the corner, sweating. Crap, I forgot to destroy the vines with a Gaster Blaster, probably because I was getting tired. They attempted to grab me again, but I snapped my fingers, and I was teleported to the other side of the room. I shouldn't of done that. I started to sweat even more. Even though it was a short distance, it still took energy, more energy than summoning a Gaster Blaster or bones. Flowey and Frisk started laughing once they saw I was getting more and more tired. I didn't let that stop me. I summoned more bones underneath them while Gaster Blasters surrounded them on top. I smiled as they got hit over and over. All of a sudden, a vine quietly sprung up behind me and wrapped around my arms, legs, torso, and even my neck. My eyes widened as thorns dug in. I tried to pull away and snap my fingers to summon more attacks, but more vines covered my hands. I couldn't create attacks without hand or arm motions. I was screwed. My left eye and hands stopped glowing, and my pupils dilated down in fear.

"Aw, what's wrong? Flowey and I make a pretty powerful team, huh?" Frisk smiled, walking over to me. I glared at them as they aimed their knife at my SOUL. I tried to break my arms free, but the thorns dug in deeper, and the knife pushed in farther but without penetrating. All of a sudden, I could feel a force trying to take over my consciousness: Flowey, but I rebelled against it. More and more thorns dug in, making me lose my concentration on driving out the force. Then, I lost control over my body. It was like having an out-of-body experience. I watched in horror as Sans's (I'm calling Sans's body when Flowey is controlling him, 'Sans' because it's easier that way, just so you don't get confused.) left eye and hands started to glow again without me telling them to. Sans stood up, and Flowey seated himself on his head. The worst part was that I couldn't do anything about it. Sans started to walk toward a room that looked like Toriel's bedroom. My white pupils disappeared once I realized what Flowey was going to make Sans do. I screamed at them to stop, but Sans continued, blowing the door to splinters with a Gaster Blaster. Toriel shot up from the chair she was sitting in and stared in horror at Sans.

"S-sans?" Toriel asked warily. Sans ignored her and smiled maniacally. His eye glowed, and he summoned bones to shoot up from underneath her. I screamed when Toriel was impaled by the bones. I collapsed, shaking to the ground at the sight of Toriel dying. "Y-you really hate m-me that much?" Toriel gasped. Tears filled my eyes, and I shook my head. She couldn't see me, though. All of her attention was on Sans. "I-I loved y-you . . ." I covered my mouth, and the tears forming at my eyes fell. I was back in my body when I started to cry. Flowey grinned down at me, Frisk doing the same. My SOUL ached as I looked at the pile of dust at my feet. I continued to sob as Frisk and Flowey snickered. I was shoved out of my body again as Flowey took over. I watched through tear-blurred eyes as Sans continued to his next victim.

I watched as every single monster in the Ruins was disintegrated into dust. Once they reached the door to exit the Ruins, Flowey let me regain control of my body, and I collapsed. I was sweating like crazy and gasping for breath. I gritted my teeth and screwed my eyes closed. Never before have I used that much magic. I didn't even have the energy to cry about all the lives I--Flowey made me take. Frisk grasped my head, making me look up at them.

"I see you're a little bone-tired?" Frisk purred. I glared at them, still struggling for air. They narrowed their eyes and smiled at me. "Here. Let me fix that." All of a sudden, I felt a rush of energy, and I bolted up. It was Frisk's DETERMINATION. My pupils dilated at the amount of energy I had and looked down to see a message saying, '2 HP'. I stared at the message incredulously. Flowey nodded approval at Frisk and they said, "Much better." I was pushed out of my body again as Flowey took over. Right before he took over again, I released the lock I had on the doors and windows of my house.